/* =========================================================
   Serotiny Robotics — Brand system
   Safety yellow : #F7B500
   Near-black    : #0A0A0B
   Panel         : #141417 / #1B1B1F
   Type          : Saira / Saira Condensed
   ========================================================= */

:root {
  --yellow: #F7B500;
  --yellow-dark: #D99A00;
  --yellow-soft: rgba(247,181,0,.14);
  --black: #0A0A0B;
  --panel: #141417;
  --panel-2: #1B1B1F;
  --panel-3: #232328;
  --ink: #ECECEE;
  --muted: #9A9AA2;
  --line: rgba(255,255,255,.10);
  --line-strong: rgba(255,255,255,.18);
  --radius: 10px;
  --radius-lg: 18px;
  --shadow-md: 0 10px 30px rgba(0,0,0,.45);
  --shadow-lg: 0 30px 70px rgba(0,0,0,.55);
  --container: 1180px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: 'Saira', system-ui, -apple-system, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  font-weight: 400;
  font-size: 16px;
  line-height: 1.65;
  color: var(--ink);
  background: var(--black);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
img { max-width: 100%; display: block; }

h1, h2, h3, h4 {
  font-family: 'Saira Condensed', 'Saira', sans-serif;
  font-weight: 700; line-height: 1.05; color: #fff;
  margin: 0 0 .4em; letter-spacing: .005em; text-transform: uppercase;
}
h1 { font-size: clamp(2.4rem, 5.2vw, 4.2rem); font-weight: 800; }
h2 { font-size: clamp(1.7rem, 3.2vw, 2.7rem); }
h3 { font-size: 1.15rem; letter-spacing: .02em; }
p  { margin: 0 0 1em; color: var(--muted); }
strong { color: var(--ink); font-weight: 600; }
.accent { color: var(--yellow); }

a { color: var(--yellow); text-decoration: none; }
a:hover { color: var(--yellow-dark); }

.container { max-width: var(--container); margin: 0 auto; padding: 0 24px; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 14px 26px; border-radius: 4px; font-weight: 600; font-size: .95rem;
  font-family: 'Saira', sans-serif; letter-spacing: .04em; text-transform: uppercase;
  border: 1px solid transparent; cursor: pointer; transition: all .16s ease;
}
.btn-primary { background: var(--yellow); color: #0A0A0B; box-shadow: 0 8px 22px rgba(247,181,0,.22); }
.btn-primary:hover { background: #ffc41f; color: #0A0A0B; transform: translateY(-1px); }
.btn-ghost { background: transparent; color: #fff; border-color: var(--line-strong); }
.btn-ghost:hover { border-color: var(--yellow); color: var(--yellow); }
.btn-sm { padding: 9px 16px; font-size: .8rem; }
.btn-block { width: 100%; padding: 16px 22px; font-size: 1rem; }

/* ---------- Header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(10,10,11,.82);
  backdrop-filter: saturate(150%) blur(10px);
  border-bottom: 1px solid var(--line);
}
.nav { display: flex; align-items: center; justify-content: space-between; height: 96px; }
.brand-logo { height: 64px; width: auto; display: block; }
.nav-links { display: flex; align-items: center; gap: 30px; }
.nav-links a { color: var(--ink); font-weight: 500; font-size: .9rem; letter-spacing: .04em; text-transform: uppercase; }
.nav-links a:hover { color: var(--yellow); }
.nav-links a.btn-primary { color: #0A0A0B; }
.nav-toggle { display: none; background: none; border: 0; cursor: pointer; width: 40px; height: 40px; flex-direction: column; justify-content: center; gap: 5px; }
.nav-toggle span { display: block; height: 2px; background: var(--ink); border-radius: 2px; transition: .2s; }

/* ---------- Hero ---------- */
.hero {
  position: relative; overflow: hidden;
  background:
    radial-gradient(1100px 520px at 80% -10%, rgba(247,181,0,.10), transparent 60%),
    linear-gradient(180deg, #0c0c0e 0%, #0A0A0B 100%);
  border-bottom: 1px solid var(--line);
}
.hero-grid {
  display: grid; grid-template-columns: 1fr 1.15fr; gap: 32px; align-items: center;
  padding: clamp(48px, 7vw, 96px) 24px;
}
.eyebrow {
  display: inline-block; color: var(--yellow); font-weight: 600; font-size: .78rem;
  letter-spacing: .16em; text-transform: uppercase; margin-bottom: 20px;
  padding: 7px 14px; border: 1px solid var(--line-strong); border-radius: 999px;
  background: var(--yellow-soft);
}
.hero h1 { margin-bottom: 18px; }
.lede { font-size: clamp(1.05rem, 1.5vw, 1.3rem); color: #c7c7cd; max-width: 36em; }
.hero-cta { display: flex; gap: 14px; flex-wrap: wrap; margin: 28px 0 30px; }
.hero-pills { list-style: none; display: flex; flex-wrap: wrap; gap: 10px; padding: 0; margin: 0; }
.hero-pills li {
  font-size: .78rem; letter-spacing: .06em; text-transform: uppercase; color: var(--muted);
  border: 1px solid var(--line); border-radius: 4px; padding: 6px 12px; background: rgba(255,255,255,.02);
}
.hero-art { position: relative; }
.hero-art img {
  width: 100%; max-width: 720px; margin: 0 auto;
  filter: drop-shadow(0 40px 55px rgba(0,0,0,.6));
}

/* ---------- Band ---------- */
.band { background: var(--yellow); color: #0A0A0B; }
.band-text {
  margin: 0; padding: 22px 0; text-align: center; color: #0A0A0B;
  font-weight: 500; font-size: clamp(1rem, 1.7vw, 1.25rem); letter-spacing: .01em;
}
.band-text strong { color: #0A0A0B; font-weight: 700; }
.spaced { font-family: 'Saira Condensed'; font-weight: 800; text-transform: uppercase; letter-spacing: .1em; }

/* ---------- Sections ---------- */
.section { padding: clamp(56px, 8vw, 104px) 0; }
section[id], #top { scroll-margin-top: 104px; }
.section-dark { background: #0d0d10; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.section-grey { background: var(--panel); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.section-head { max-width: 760px; margin: 0 auto clamp(36px, 5vw, 60px); text-align: center; }
.section-kicker {
  display: inline-block; color: var(--yellow); font-weight: 700; font-size: .8rem;
  letter-spacing: .16em; text-transform: uppercase; margin-bottom: 14px;
}
.section-kicker::before { content: "▸ "; }
.section-sub { font-size: 1.08rem; color: var(--muted); margin-top: 12px; }
.light { color: #fff !important; }

/* ---------- Problem grid ---------- */
.problem-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; }
.problem-card {
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 26px 22px; position: relative; transition: border-color .18s, transform .18s;
}
.problem-card:hover { border-color: var(--yellow); transform: translateY(-3px); }
.problem-num {
  font-family: 'Saira Condensed'; font-weight: 800; font-size: 2.2rem; color: var(--yellow);
  line-height: 1; margin-bottom: 14px;
}
.problem-card p { margin: 0; font-size: .98rem; }

/* ---------- ANUBIS ---------- */
.anubis-grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: 50px; align-items: center; }
.anubis-art img { filter: drop-shadow(0 30px 50px rgba(0,0,0,.6)); }
.cap-list { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 18px; }
.cap-list li { display: flex; gap: 14px; align-items: flex-start; }
.cap-mark { color: var(--yellow); font-weight: 700; line-height: 1.4; }
.cap-list strong { display: block; color: #fff; font-size: 1.05rem; }
.cap-list span { color: var(--muted); font-size: .95rem; }

/* ---------- Terrain ---------- */
.terrain-grid { display: grid; grid-template-columns: .9fr 1.1fr; gap: 50px; align-items: center; }
.terrain-art img { border-radius: var(--radius-lg); margin: 0 auto; }
.tick-list { list-style: none; margin: 18px 0 0; padding: 0; display: grid; grid-template-columns: 1fr 1fr; gap: 10px 24px; }
.tick-list li { position: relative; padding-left: 26px; color: var(--ink); font-size: .98rem; }
.tick-list li::before {
  content: "✓"; position: absolute; left: 0; top: 0; color: #0A0A0B; background: var(--yellow);
  width: 18px; height: 18px; border-radius: 3px; display: grid; place-items: center; font-size: .7rem; font-weight: 700;
}

/* ---------- How steps (In the field) ---------- */
.how-steps { list-style: none; counter-reset: step; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; }
.how-steps li { background: var(--panel-2); border: 1px solid var(--line); border-radius: var(--radius); padding: 26px 22px; }
.step-num {
  font-family: 'Saira Condensed'; font-weight: 800; font-size: 1.4rem; color: #0A0A0B;
  background: var(--yellow); width: 44px; height: 44px; border-radius: 6px; display: grid; place-items: center; margin-bottom: 16px;
}
.how-steps h3 { color: #fff; }
.how-steps p { margin: 0; font-size: .95rem; }
.solution-tagline {
  text-align: center; margin: clamp(34px,5vw,52px) auto 0; max-width: 720px;
  font-family: 'Saira Condensed'; font-weight: 700; text-transform: uppercase; letter-spacing: .03em;
  font-size: clamp(1.1rem, 2vw, 1.5rem); color: #fff;
}

/* ---------- Business model ---------- */
.model-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 18px; }
.model-card { background: var(--panel); border: 1px solid var(--line); border-left: 3px solid var(--yellow); border-radius: var(--radius); padding: 28px 26px; }
.model-card h3 { color: #fff; }
.model-card p { margin: 0; }
.plus { color: var(--yellow); font-weight: 700; padding: 0 4px; }

/* ---------- CTA / form ---------- */
.section-cta {
  background:
    radial-gradient(800px 400px at 12% 0%, rgba(247,181,0,.10), transparent 60%),
    #0d0d10;
  border-top: 1px solid var(--line);
}
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 50px; align-items: start; }
.contact-copy h2 { margin-bottom: 14px; }
.contact-list { list-style: none; padding: 0; margin: 22px 0 0; display: flex; flex-direction: column; gap: 12px; }
.contact-list li { padding-left: 22px; position: relative; color: var(--muted); }
.contact-list li::before { content: "▸"; position: absolute; left: 0; color: var(--yellow); }
.contact-list strong { color: #fff; }

.contact-form {
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius-lg);
  padding: 30px; box-shadow: var(--shadow-lg);
}
.contact-form label { display: block; font-size: .85rem; font-weight: 600; color: var(--ink); margin-bottom: 14px; letter-spacing: .02em; }
.contact-form .opt { color: var(--muted); font-weight: 400; text-transform: none; }
.contact-form input, .contact-form select, .contact-form textarea {
  width: 100%; margin-top: 7px; padding: 12px 14px; font-size: .98rem; font-family: inherit;
  border: 1px solid var(--line-strong); border-radius: 6px; background: #0c0c0e; color: var(--ink);
}
.contact-form input:focus, .contact-form select:focus, .contact-form textarea:focus {
  outline: none; border-color: var(--yellow); box-shadow: 0 0 0 3px var(--yellow-soft);
}
.contact-form textarea { resize: vertical; }
.contact-form .btn-block { margin-top: 6px; }
.form-note { font-size: .82rem; color: var(--muted); margin: 14px 0 0; text-align: center; }
.hp { position: absolute; left: -5000px; }

/* ---------- Footer ---------- */
.site-footer { background: #08080a; border-top: 1px solid var(--line); padding: 48px 0; }
.footer-inner { display: flex; justify-content: space-between; gap: 30px; flex-wrap: wrap; align-items: flex-start; }
.footer-logo { height: 54px; width: auto; margin-bottom: 14px; }
.footer-brand { max-width: 460px; }
.footer-brand p { font-size: .92rem; }
.footer-meta { text-align: right; }
.footer-meta p { font-size: .9rem; margin: 0 0 6px; }

/* ---------- Responsive ---------- */
@media (max-width: 920px) {
  .nav-links {
    position: absolute; top: 96px; left: 0; right: 0; flex-direction: column; gap: 0;
    background: #0c0c0e; border-bottom: 1px solid var(--line); padding: 8px 0; display: none;
  }
  .nav-links.open { display: flex; }
  .nav-links a { width: 100%; padding: 14px 24px; }
  .nav-links a.btn-primary { margin: 8px 24px; width: auto; justify-content: center; }
  .nav-toggle { display: flex; }
  .hero-grid { grid-template-columns: 1fr; }
  .hero-art { order: -1; max-width: 560px; margin: 0 auto; }
  .anubis-grid, .terrain-grid, .contact-grid { grid-template-columns: 1fr; gap: 32px; }
  .terrain-art { order: -1; max-width: 420px; }
  .problem-grid, .how-steps { grid-template-columns: 1fr 1fr; }
  .model-grid { grid-template-columns: 1fr; }
  .footer-inner { flex-direction: column; }
  .footer-meta { text-align: left; }
}
@media (max-width: 540px) {
  .problem-grid, .how-steps, .tick-list { grid-template-columns: 1fr; }
  .brand-logo { height: 50px; }
  .nav { height: 76px; }
  .nav-links { top: 76px; }
}